Diffuse Alveolar Hemorrhage

Brandi R. Newsome, MD; Juan E. Morales, MD


South Med J. 2011;104(4):269-274. 

In This Article

Abstract and Introduction


Diffuse alveolar hemorrhage (DAH) is a life-threatening disorder characterized clinically by the presence of hemoptysis, falling hematocrit, diffuse pulmonary infiltrates and hypoxemic respiratory failure. It refers to bleeding that originates in the pulmonary microvasculature instead of the parenchyma or bronchial circulation. DAH should be considered a medical emergency due to the morbidity and mortality associated with failure to treat the disorder promptly. Pulmonary renal syndromes, connective tissue disorders and drugs make up the majority of the cases of DAH. The treatment of DAH ranges from supportive care and withdrawal of offending drugs to high-dose steroids, immunosuppresents and plasmapharesis. The following review will discuss the clinical, radiographic and pathologic findings in a variety of disorders that cause DAH. Standard treatment options, as well as new treatment options will also be discussed.


Diffuse alveolar hemorrhage (DAH) is a life-threatening condition which refers to hemorrhage originating in the pulmonary microvasculature, rather than from the bronchial circulation or parenchymal abnormalities. The clinical syndrome is characterized by hemoptysis, falling hematocrit, hypoxemic respiratory failure and diffuse pulmonary infiltrates.[1] DAH should be considered a medical emergency due to the significant morbidity and mortality associated with delayed treatment. While the differential diagnosis is broad, the majority of cases of DAH are caused by a relatively small number of conditions listed in Table 1.[1] A retrospective review of 34 cases of DAH revealed nearly one-third of the cases were caused by Wegener granulomatosis.[2] Making the diagnosis requires the clinician to understand the basic clinical presentation, laboratory findings and diagnostic criteria.


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